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Questions: How did the vegetation of a Central European mountain region with a fragmented alpine zone develop during the Holocene? When did human land use start to alter summit grasslands? Which gradient in pollen assemblages was strongest and was it consistent through time? Location: Jeseníky Mountains, Czech Republic. Methods: Sixteen pollen records were subjected to DCA in order to explore patterns of compositional similarities in the fossil pollen data. Because only the last 6,000 years were recorded in the study sites from mountain summits, we restricted further analysis to this period. Twelve radiocarbon-dated pollen records were subjected to DCCA constrained by modelled calibrated age. Responses of individual pollen types to the principal DCCA gradients were tested with GAMs. Results: In the DCA, Early Holocene samples were located close to recent ones due to abundant pollen of herbs, Poaceae, Betula, Pinus sylvestris type and rare pollen of climax deciduous trees. In the DCCA for the last 6,000 years, the sorting of sites along the first unconstrained axis correlated with altitude, which is a complex factor corresponding to temperature and geomorphology (flat summits vs alluvia of mountain rivulets). This elevational differentiation became more pronounced after 2,250 cal BP when summit peatlands started to contain more Vaccinium, Calluna vulgaris, Amaranthaceae, Plantago lanceolata and Rumex acetosa type pollen. In contrast, mid-elevation pollen spectra started to contain more meadow herbs (Caltha, Potentilla type, Cirsium/Carduus). Picea pollen was surprisingly more associated with mid-elevation than high-elevation sites, unlike Fagus. Conclusion: Increasing contrast between summits and middle elevation alluvia seems to be a major feature of vegetation development over the last 6,000 years. While alluvial areas were encroached by Alnus-Picea forests, and later locally transformed into wet grasslands, grazing and forest burning at summits gradually increased abundance of acidophytic dwarf shrubs and peatlands, especially since the Iron Age. Human impact might facilitate beech expansion at high elevations, with Picea-dominated forests being restricted to alluvia and around mid-elevation basin peatlands prior to establishment of modern Picea plantations.

The climatic changes that took place in Europe during the Quaternary period influenced plant habitats as well as their species and vegetation composition. In this article, biogeographical studies on Hercynian mountain plants that include data for the Alps, Carpathians, and European lowlands are reviewed in order to discuss the phylogeographical structure and divergence of the Hercynian populations from those in other European mountain ranges, Scandinavia, and lowlands. The analyzed studies show specific phylogeographical relations between the Hercynian mountains, Alps, Scandinavia, Carpathians, and European lowlands. The results also indicate that the genetic patterns of plant populations in the Hercynian Mountains may differ significantly in terms of origin. The main migration routes of species to the Hercynian ranges began in the Alps or Carpathians. Some species, such as Rubus chamaemorus L., Salix lapponum L., and Salix herbacea L., are glacial relics that may have arrived and settled in the Hercynian Mountains during the Ice Age and that survived in isolated habitats. The Hercynian Mountains are composed of various smaller mountain ranges and are a crossroads of migration routes from different parts of Europe; thus, intensive hybridization has occurred between the plant populations therein, which is indicated by the presence of several divergent genetic lines.

Kwiatkowski P.: Chorological and phytogeographical diversity of trees and shrubs as a mean to regionalization: Kaczawa Mountains, Sudetes, Poland. — Willdenowia 44: 363–376. 2014. — Version of record first published online on 10 November 2014 ahead of inclusion in December 2014 issue; ISSN 1868-6397; © 2014 BGBM Berlin-Dahlem. DOI: http://dx.doi.org/10.3372/wi.44.44306 The tree and shrub flora of the Kaczawa Mountains (Sudetes, Poland) consists of 240 taxa, of which over 70 % are native. The biodiversity and chorological differentiation are reflected in a number of biogeographical phenomena, such as differences in floristic richness of native and alien species, concentration of borderline species, and co-occurrence of various taxa. Concentration maps of particular groups of taxa in the investigated area together with the statistical analysis point to distinct relationships between the distribution of these groups and earlier recognized phytogeographical units of the rank of three subdistricts (Kaczawa Mountains, Western Kaczawa Plateau, Eastern Kaczawa Plateau), which include eight geobotanical sections. The distinguished phytochorions cover territories of various areas demarcated by natural borders and characterized by specific components of woody flora, concentration of taxa exhibiting particular types of local geographical range, as well as by altitude, relief, geological structure, and local climatic and hydrological parameters.

Black shales and massive sulfides represent reduced lithofacies that require isolation from oxic environments to be preserved. This, together with the sedimentary affinity of both lithofacies, can explain their common concurrence in the geologic record. The present study is based on the comparison of Rammelsberg in Germany, Tharsis in Spain, and Draa Sfar in Morocco, three massive sulfide deposits closely associated with black shales that are distributed along the European and North African Variscan orogen. The study entails geochemical, biostratigraphic, and stratigraphic analyses of the black shale sequences hosting the three deposits and mineralogical and textural analyses of the sulfides. All three deposits were formed in immature, tectonically unstable basins within an active continental margin or continental magmatic arc. Their stratigraphic records consist of a sequence of black shales enclosing massive sulfides and variable proportions of bimodal volcanic and subvolcanic rocks. The major differences among the three deposits concern the size, composition, and mineralogy. Regarding age, they are diachronous and younger southward: Rammelsberg is middle Eifelian, Tharsis latest Famennian, and Draa Sfar late Viséan. The study of redox conditions of the paleoenvironment using organic and inorganic proxies highlights similarities and significant differences among the three ore-hosting basins during massive sulfide and black shale deposition. The black shales generally display low C org and high S tot contents. At Rammelsberg, the S tot /C tot ratios provide values typical for normal Middle Devonian marine environments, which suggests that the original reactive organic C is now fixed in carbonates. At Tharsis, most of the samples have C org >1 and S tot /C org values equivalent to those of Devonian–Carboniferous normal marine sediments. However, some pyritic hanging-wall samples have C org <1 and S tot up to 5 wt.%, suggesting the epigenetic addition of HS − . The S tot /C org ratio for the Draa Sfar samples resembles that of Middle Carboniferous normal marine environments. Geochemical inorganic proxies used to define the environmental conditions include the enrichment factors of U (U EF ) and Mo (Mo EF ) together with V/Cr and V/(V + Ni) ratios. Footwall shales at Filón Norte (Tharsis) show positive and eventually elevated U EF and Mo EF values, which suggests anoxic conditions, whereas at Rammelsberg and Draa Sfar oxic bottom water is indicated. The relations V/Cr and V/(V + Ni) in all three cases point to a redox boundary near the sediment–water interface, although at Tharsis some samples indicate anoxic/euxinic conditions (i.e., V/(V + Ni) >0.9). Regarding the environmental conditions of the source areas, feldspar illitization and selective depletion in Na and Ca occurred at the three studies sites. Available sulfur isotopic data from the Rammelsberg and Tharsis sulfide ore indicate that biogenic reduction of marine sulfate was a major sulfur source during massive sulfide generation. Nevertheless, a hydrothermal sulfur source has also been detected. At Rammelsberg, this is indicated from the polymetallic sulfides that replace sedimentary and diagenetic pyrite. At Tharsis, the bacteriogenic sulfur signature is also restricted to sulfide with less evolved textures, whereas a hydrothermal source is more evident in sulfides showing evidence of recrystallization. Both geochemical and isotopic data suggest that the bacteriogenic reduction process was inhibited by rapid burial. The sedimentation rates calculated for Rammelsberg, Tharsis, and Draa Sfar were in the range 7–13, 8–14, and 19–27 cm/ka, respectively. Continuous sedimentation of black shale favored the isolation of the massive sulfides and organic material from bottom waters and hence favored their preservation. Accordingly, the relationships between black shales and massive sulfides are considered to be casual. Nevertheless, the tectono-sedimentary evolution of each basin controlled the deposition of both black shales and massive sulfides and the parameters that favored their coeval deposition.

Electrical resistivity of the Earth’s crust is sensitive to a wide range of petrological and physical parameters, and it particularly clearly indicates crustal zones that have been tectonically or thermodynamically disturbed. A complex geological structure of the Alpine nappe system, remnants of older Hercynian units and Neogene block tectonics in Western Slovakia has been a target of recent magnetotelluric investigations which made a new and more precise identification of the crustal structural elements of the Western Carpathians possible. A NW-SE magnetotelluric profile, 150 km long, with 30 broad-band and 3 long-period magnetotelluric sites, was deployed, crossing the major regional tectonic elements listed from the north: Brunia (as a part of the European platform), Outer Carpathian Flysch, Klippen Belt, blocks of Penninic or Oravicum crust, Tatricum and Veporicum. Magnetotelluric models were combined with previous seismic and gravimetric results and jointly interpreted in the final integrated geological model. The magnetotelluric models of geoelectrical structures exhibit strong correlation with the geological structures of the crust in this part of the Western Carpathians. The significant resemblance in geoelectrical and crustal geological structures are highlighted in shallow resistive structures of the covering formations represented by mainly Tertiary sediments and volcanics. Also in the deeper parts of the crust highly resistive and conductive structures are shown, which reflect the original building Hercynian crust, with superposition of granitoids or granitised complexes and lower metamorphosed complexes. Another important typical feature in the construction of the Western Carpathians is the existence of young Neogene steep fault zones exhibited by conductive zones within the whole crust. The most significant fault zones separate individual blocks of the Western Carpathians and the Western Carpathians itself from the European Platform.

New results related to the thickness and density of the sedimentary fill of the Turiec Basin allowed us to construct the first original stripped gravity map for this typical intramontane Neogene depression of the Western Carpathians. The stripped gravity map of the Turiec Basin represents the Bouguer gravity anomalies corrected for the gravity effect of the density contrast of its Quaternary-Tertiary sedimentary basin fill. It means that the map reflects the gravity effects of the density inhomogeneities which are located beneath the sedimentary basin fill. This map is therefore suitable for the interpretation of the structure and composition of the pre-Tertiary basement. Based on the new data analysis, two different density models of the sedimentary fill were constructed. The 3D density modelling was used to calculate the gravity effect of the density models. The stripped gravity maps were produced by subtracting the density model gravity effects from Bouguer anomalies. The regional trend was also removed from the stripped gravity maps. The residual stripped gravity maps were consequently used for geological interpretation of the pre-Tertiary basement of the Turiec Basin. The pre-Tertiary basement of the Turiec Basin can be divided into northern and southern parts due to its gravity characteristics. Furthermore the northern part can be split into two domains: western and eastern. The crystalline basement of the western domain is probably formed by the Hercynian crystalline basement of the Tatric Unit. In the eastern domain the basement could consist mostly of the Mesozoic complexes of the Fatric Unit. The southern part of the pre-Tertiary basement of the Turiec Basin is built predominantly by Mesozoic complexes of the Hronic Unit. It is suggested that the Hronic Unit also forms the bedrock of the volcano-sedimentary complex of the Kremnické vrchy Mts. The resultant stripped gravity maps and the map of total horizontal gravity gradients have also proven to be very useful for the interpretation of faults or fault systems in the study area. Various faults, particularly of NNE-SSW and NW-SE directions were discovered. The analysis of the faults indicates clearly that the contact of the Turiec Basin with the Malá Fatra Mts and the Veľká Fatra Mts is tectonic.

Located in the southern part of the Western Alps, the Argentera massif belongs to the paleo-European basement of the external domain. It experienced a polyphased deformation history, Hercynian and Alpine. The Alpine history is characterized by the development of a network of ductile shear zones. An 39Ar−40Ar study of single grains of Hercynian muscovites and Alpine phengites allowed to constrain various events. A muscovite cooling age at ca 296-299 Ma is proposed for the Argentera granite, clearly later than the estimated cooling age at ca 310-315 Ma for the low-pressure anatexis. Neocrystallized phengites collected within an Alpine shear zone (Frema Morte) crosscutting the late Hercynian Argentera granite yielded an age at 22.2 ± 0.3 Ma (1σ). This is one of the first unequivocal absolute age constraint of a late Alpine metamorphism in the external crystalline massifs of the Western Alps. Our P-T conditions estimates indicate a regional temperature at ca 350°C for pressure at 0.35-0.4 GPa for this Alpine metamorphism. These estimates imply a minimum burial of 14 km for the Argentera massif, which could result from the overloading imposed by the internal nappes emplacement, probably between 28 Ma and 22.2 Ma.

In this study, two small but genetically related iron carbonate deposits Macje Jame and Vranjski Potok, south west of Busovaca, located in the pre-Devonian metamorphic complex were investigated in detail. Analyses of the main chemical components, trace elements, REE, isotope composition of C, O, S, 87Sr/86Sr ratio of rhyolite, plot of REE normalized to CI chondrites and a microscopic study of thin and polished sections were performed. Three mineralization phases were identifi ed: the oldest is the main phase with Fe (Ca, Mg, Mn) carbonates (siderite, ankerite, Fe-dolomite) as the predominant minerals, whereas magnetite, haematite, albite, allanite, pyrite I, quartz I represent subordinate minerals. This claim is strongly supported by very similar REE and their interior disposition between these deposits and metarhyolites as well as by the obtained strontium ratios. The third, youngest phase is the product of a very weak overprint of hydrothermal activity in the Late Variscan and in the Upper Permian-Lower Triassic.

Accessory Fe-rich columbite-group minerals, tapiolite and Hf-rich zircon occur in Hercynian pegmatitic leucogranite near Duchonka, Povazský Inovec Mts., western Slovakia. The host rock represents highly peraluminous and fractionated S-type pegmatitic leucogranite with ASI = 1.27, Eu^sub N^/Eu*^sub N^ = 0.16, Rb/Sr = 7.2, Ta/Nb = 1.1 and Zr/Hf= 21, but not enriched in Li, B, Be or P. Columbite-tantalite, tapiolite and hafnian zircon form discrete crystals, 30 to 350 µm in size, in association with quartz, plagioclase, K-feldspar, muscovite, sillimanite, almandine-spessartine and fluorapatite. Columbite-tantalite crystals show coarse oscillatory zoning, usually with border parts enriched in Ta. Locally, there is a reversal trend of zoning (decrease of Ta towards the border parts), or irregular convoluted zoning as a result of late-magmatic to subsolidus dissolution-reprecipitation. The composition of columbite-tantalite shows a relatively constant Mn/(Mn + Fe) ratio (0.20-0.27, locally 0.35-0.40), but extreme variations of the Ta/(Ta + Nb) ratio (0.18-0.72). Ratios higher than 0.63 plot inside the tantalite-tapiolite miscibility gap. Ferrotapiolite is mainly homogenous and shows relatively consistent compositions with Mn/(Mn + Fe) = 0.03-0.04 and Ta/(Ta + Nb) = 0.88-0.97. Metamict zircon (5 to 120 µm in size) exhibits tiny uraninite inclusions, high Hf contents (6 to 23 wt. % HfO^sub 2^, 0.06-0.23 Hf apfu), and locally elevated P, As and U contents, whereas Y and REE concentrations are low. Unusually widely variable and high Ta/Nb and Hf/Zr ratios in the accessory minerals are probably the product of extreme local Nb-Ta and Zr-Hf fractionation in highly peraluminous granite-pegmatite system. [PUBLICATION ABSTRACT]

The Peloritani Mountains are a fragment of an orogen variably attributed to the Alpine or Hercynian orogeny. On the basis of ^sup 39^Ar-^sup 40^Ar, U-Pb and Rb-Sr dating, the main metamorphism of the two medium-high grade metamorphic units, the Mela and Aspromonte Units, and most of the thrusting responsible for stacking the orogenic edifice are seen to be Hercynian. The main thrusting of the Aspromonte Unit over the lower grade units took place at 301±2 Ma. Brittle deformation during Tertiary reactivation of Hercynian thrust planes did not generate any rejuvenation of white micas in the studied sector. Our dataset shows a great complexity and we propose to unravel it by considering different levels of information. To first order, the Mela and Aspromonte Units differ in their metamorphic paths and their geochronological evolution. The Mela Unit shows generally younger ages (Carboniferous) than the Aspromonte Unit and, unlike the latter, was extensively retrogressed in greenschist facies. The Aspromonte Unit is itself geochronologically heterogeneous. Proterozoic ages are preserved both in titanite and in amphibole relics of one tectonic subunit; Devonian to Carboniferous amphibole ages are found in different other subunits; tertiary overprint is minor and spatially limited. We propose to consider the chronologically heterogeneous subunits as accreted pre-Hercynian terranes amalgamated late during the Hercynian orogeny. Micas in both units give scattered Mesozoic ^sup 39^Ar-^sup 40^Ar and Rb-Sr ages, with evidence for heterochemical mica generations. We interpret them as a result of widespread hydrothermal circulation event(s). Tertiary overprint is generally absent, with the exception of a small area near Messina where biotite and muscovite underwent a complex recrystallisation history in the interval between 48 and 61 Ma.[PUBLICATION ABSTRACT] Erratum DOI: 10.1007/s00531-004-0380-0